My computer keeps shutting down

Hello everyone

My computer keeps shutting down. It is very frustrating and there seems to be no pattern so I'm hoping someone out there can help me. OS - Vista Ultimate 32 running AVG free (latest version), Firefox.

This has only happened since the installation of service pack 2 and haven't, as yet, taken it back to 1 yet.

It seems to just go off when I either do a scan (AVG), run sims 3, or do something that requires dl/ul, ie pictures from camera, update of ipod library. I've checked that the fans are all ok and the heat of the CPU is about 26 degrees. Its an AMD Athlon 64 Dual Core 6000+.

I am currently checking for malware with malwarebytes as I type this. Still scanning C but nothing coming up as of yet.

Can anyone suggested anything else? Is there any particular information you need?

hi,,, looking at the things you say causes the event, i would have said it was heat,,,, as most of these things are intensive programs,,, and would have suggested a good clean out with a can of compressed air,,,, but the temps you are seeing say other wise,,,,,, run scans with your A/V and download malwarebytes free version,,, update it and run a full scan,,,,, while your scanning open task manager and see how much cpu your using and if it stays at around 100% as this will cause a shutdown too,,,, also type ,,, event viewer ,,, into tearch box in start menu and hit enter ,,, take a look in critical and error in event viewer to see if this will shed some light on it,,,
good luck.

Thanks, Figgis, i'll get onto that all right away. Keep you posted.